It plays a part in my opinion. I found most of the dead ghosts because I actually care about the story. And we all know that there isn't much of a story in-game. If I see someone that has high grimore, that should mean that they've been playing for a while and that they are interested in the game's story. It shows experience. A person with 2800 grimore, probably isn't going to be as experienced as someone with 4700.